fcr Acc. pump help


7 replies to this topic
  • foxz

Posted July 23, 2008 - 04:52 PM

#1

Hello, im trying to get rid of the bog in my 426..was going too do the o-ring mod..Do i have to fiddle wit hthe acc. pump timing screw? i was playing with it and pressed all the way in the duration is 3/4 ish of a second...where it was stock its about 3.5... hardware stores are closed so ill have to go tomarrow, but will the O ring with the stock position on the timming be right? Kind of confused. Any help would be great! thanks.

  • WB450

Posted July 23, 2008 - 06:59 PM

#2

Hope this helps.

http://motoman393.th.../tech/carb.html

  • foxz

Posted July 23, 2008 - 08:46 PM

#3

thanks. works wonders!

  • 426

Posted July 24, 2008 - 05:55 AM

#4

Am I right, but basically, this mod is only to limitate the accel pump movement? What's the point doing this? I mean, is the pump timed too long from factory? Is there some cons about it?Thanks

I was planning on doing this mod but I want to be sure it really is useful and it's not a fix-a-thing-create-another-problem kind of mod

:ride:

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  • grayracer513

Posted July 24, 2008 - 06:07 AM

#5

Am I right, but basically, this mod is only to limitate the accel pump movement? What's the point doing this? I mean, is the pump timed too long from factory?

Yes..

  • 426

Posted July 24, 2008 - 06:18 AM

#6

I see... Thanks:thumbsup:

  • Demo_Slug

Posted July 24, 2008 - 11:17 AM

#7

Yes..


;) But….. I thought the O-ring increased the spring rate? The AP bladder is compressed by a spring force. More spring equals stronger squirt? I think zip ty has a stronger spring for the AP circuit if you want something more elaborate then an oring. am I wrong or just miss reading the post :ride:

  • grayracer513

Posted July 24, 2008 - 11:27 AM

#8

;) But….. I thought the O-ring increased the spring rate? The AP bladder is compressed by a spring force. More spring equals stronger squirt? I think zip ty has a stronger spring for the AP circuit if you want something more elaborate then an oring. am I wrong or just miss reading the post :ride:

If you read the mod in question here, you will not see an O-ring used. This is a timing mod for the 426, and has nothing to do with any of the 450's, although they can also end up suffering from an overlong pump squirt if the tweakers get carried away. The trouble with the 426 is that the squirt just went on forever unless it was limited.



You are correct about the function of the O-ring mod, and that the heavier springs now available are a more workmanlike approach.





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